Thermographic apparatus has been used for diagnosing the degree of blood circulation in the limbs of people. For example, U.S. Pat. No. 4,379,461 discloses a thermographic apparatus which uses an infrared detector carried on a linkage which is moved along the patient's limb to determine the temperature profile along the limb in evaluating the circulation in the limb. However, that device has not been adapted for use in evaluating the circulation in a person's foot. Although there are very costly computerized devices for evaluating blood circulation, they are not usable in the field such as shoe stores or any other facility concerned with orthopedic examination where an inexpensive but reliable source in evaluating foot shape and blood circulation is required, so that the proper shoe and/or treatment can be prescribed for the customer.
Devices, which have been used in evaluating the anatomical shape of a person's foot, are disclosed in U.S. Pat. Nos. 2,009,340, 2,096,615, 2,325,490, 2,382,131 and 2,480,361. U.S. Pat. No. 2,325,490 discloses a stand having a transparent foot support of glass with a slanted mirror located beneath the foot support. A camera is positioned exterior of the stand and the mirror angled relative to the foot support to permit photographing the shape of the person's foot in evaluating the physical pressure points of the foot. Another foot visualizer is disclosed in U.S. Pat. No. 2,382,131. A dual mirror arrangement is provided to enable viewing of the person's foot shape and characteristics from above the unit. A similar device is disclosed in U.S. Pat. No. 2,480,361 where elongate lamps are provided beneath the foot stand to illuminate and thereby show to the viewer the condition of the person's foot.
Liquid crystal temperature indicators have been used in measuring human body temperatures as disclosed in U.S. Pat. Nos. 3,993,809 and 4,302,971. A special film construction is provided in U.S. Pat. No. 3,993,809 to provide elasticity in the film for location on contoured parts of the body so that the film may be flexed and thereby conformed to provide proper indication of body temperature. To alleviate this problem, U.S. Pat. No. 4,302,971 discloses liquid crystal temperature indicator which is of a reduced size so that it may be readily located on the planar portion of the person's forehead to indicate body temperature.
The apparatus, according to this invention, provides an economical arrangement which readily indicates the condition of the person's foot to assist the user in selecting proper foot wear and/or treatment to improve foot condition. Because of its simplicity and economy in manufacture, the device can be readily used in most normal shoe stores or orthopedic shoe stores and other centres which evaluate foot condition.